Changes in meat quality and volatile flavor compounds profile in beef loin during dry-aging

The objective of this study was to evaluate the effects of dry-aging on beef meat quality changes and flavor compound developments during dry-aging periods. The results showed increased pH and weight loss (P < 0.01), while decreased water content, drip loss, centrifugation loss, and cooking loss (P < 0.01) with dry-aging. The extension of dry-aging significantly improved shear force and myofibrillar protein fragmentation (P < 0.05) of beef loins. However, longer-term dry-aged (28 d) meat exhibited much lower a* values, and higher 2-thiobarbituric reactive substances and carbonyl content (P < 0.01) at the end of dry-aging and even subsequent display. A total of 62 volatile flavor compounds were detected with whole dry-aging periods, and aldehydes were the major potential contributors to cooked beef meat flavor. Principal component analysis indicated the difference in flavor compounds profiles between unaged and dry-aged beef. The content of Strecker aldehydes (2-methyl-butanal and 3-methyl-butanal), some acids, heterocyclic compounds, and ethyl acetate increased with the prolongation of dry-aging time. By combining partial least squares discrimination analysis, 34 compounds with variable importance projection (VIP) > 1 were screened as important aroma compounds changed during the dry-aging processing of beef.